A United Nations panel has determined that Julian Assange has been arbitrarily detained at the Ecuadorian embassy in London, where the WikiLeaks founder has been living since 2012. In a report published today, the UN Working Group on Arbitrary Detention (UNWGAD) said that Sweden and the UK should compensate Assange for the detention, though the ruling is not legally binding. British authorities have said they will arrest Assange if he leaves the embassy. On Friday, British Foreign Secretary Philip Hammond described the panel's decision as "frankly ridiculous," saying the government rejects it.

Swedish authorities have sought to question Assange, 44, on an accusation of rape, but the Australian national has denied the claim and fears extradition to the US, where he could face charges related to the troves of diplomatic cables that WikiLeaks began publishing in 2010.

In a statement released Friday, the UNWGAD said that Sweden and the UK should work to guarantee Assange's "safety and physical integrity, to facilitate the exercise of his right to freedom of movement in an expedient manner, and to ensure the full enjoyment of his rights guaranteed by the international norms on detention." Assange's legal team filed a complaint with the panel in 2014, saying that being confined to the embassy had taken a "significant toll" on his health.

In a statement published to the WikiLeaks Twitter account this week, Assange said he should be allowed to leave the embassy if the panel ruled in his favor. This week, Sweden said it would reject the panel's findings and continue to pursue extradition, though Assange's lawyers are hopeful that the UN decision will pressure authorities to change its position.

"To go against a decision would be to go against a unit of the United Nations, and their own interpretation of human rights," Per Samuelsson, a lawyer for Assange, told The New York Times yesterday. "In that case, it would be for the Swedish prosecutor to cancel the decision and withdraw the European arrest warrant."

At a press conference held in London following the UNWGAD's announcement, Assange described the decision as "a really significant victory that has brought a smile to my face, and I hope many others as well." Speaking to reporters from the Ecuadorian embassy, he went on to criticize the refusal from Sweden and the UK to recognize the decision, saying their continued resistance "would have the effect of undermining the UN system."

"While I understand the momentary political imperatives for representatives of Sweden and the UK to look like they were correct in their earlier, unlawful decisions, the fact is that they are not," Assange said. "There has been a final decision. There is no ability to appeal the decision of the UN. The lawfulness of my detention... is now a matter of settled law."

The BBC first reported on the UN decision Thursday.

This article has been updated to include comments from Julian Assange's press conference.